1. Technical Field
Embodiments relate to a semiconductor device and a manufacturing method thereof, and more particularly, to a semiconductor device capable of reducing coupling capacitance between a bit line and a storage contact plug and between a bit line contact and the storage contact plug, and a manufacturing method thereof.
2. Related Art
Semiconductor devices are manufactured using various processes, for example, ion implantation, thin film deposition, or the like. The semiconductor devices include elements such as transistors, capacitors, and resistors and these elements are coupled through conductive layers to transmit and/or receive data or signals.
As manufacturing technology for semiconductor devices has developed, the minimum feature size of structures in the semiconductor devices is reduced to improve the degree of integration.
In a semiconductor device in which a size of a unit cell is 6F2 (F: minimum feature size), an active region has an elliptic shape in which a major axis of the active region is tilted at an angle with respect to a direction along which a bit line extends. The semiconductor device includes a word line that has a gate structure, which is buried in a semiconductor substrate.
In the semiconductor device of a 6F2 structure, a bit line contact is connected to an active region, which is formed between neighboring buried gates, and a bit line is stacked on the bit line contact to be connected to the bit line contact. Storage node contacts are connected to both end portions of the active region.
However, as a highly integrated semiconductor device has developed, the size of a unit cell of the semiconductor device is reduced, and thus a distance between the bit line and the storage node contact plug and a distance between the bit line contact and the storage node contact plug is reduced.
Therefore, coupling capacitance between the bit line and the storage node contact plug and between the bit line contact and the storage node plug is increased in a highly integrated semiconductor device.